Search results
Results From The WOW.Com Content Network
The name was also chosen to continue the tradition of the four stable halogens, where the name referred to a property of the element. [97] Corson and his colleagues classified astatine as a metal on the basis of its analytical chemistry. [98] Subsequent investigators reported iodine-like, [99] [100] cationic, [101] [102] or amphoteric behavior.
The rarest elements in the crust are not the heaviest, but are rather the siderophile elements (iron-loving) in the Goldschmidt classification of elements. These have been depleted by being relocated deeper into the Earth's core; their abundance in meteoroids is higher.
The abundance of the chemical elements is a measure of the occurrences of the chemical elements relative to all other elements in a given environment. Abundance is measured in one of three ways: by mass fraction (in commercial contexts often called weight fraction), by mole fraction (fraction of atoms by numerical count, or sometimes fraction of molecules in gases), or by volume fraction.
The name iridium, derived from the Greek word iris (rainbow), refers to the various colors of its compounds. Iridium is one of the rarest elements in Earth's crust , with an estimated annual production of only 6,800 kilograms (15,000 lb) in 2023.
It is one of the rarest and most valuable precious metals. Rhodium is a group 9 element (cobalt group). Rhodium is found in platinum or nickel ores with the other members of the platinum group metals. It was discovered in 1803 by William Hyde Wollaston in one such ore, and named for the rose color of one of its chlorine compounds.
In the universe, thorium is among the rarest of the primordial elements at rank 77th in cosmic abundance [74] [79] because it is one of the two elements that can be produced only in the r-process (the other being uranium), and also because it has slowly been decaying away from the moment it formed.
Rare and expensive; used in jumpgates; forms when ordinary matter is subject to the stresses of a supernova, pushing some of its electron pair-bonds into hyperspace. The most commonly found form derives from 40 K, giving quantium-40. The name was coined by David Strauss in response to a request from the show's creator. [99]
With an estimated average concentration of 1 part per billion (ppb), rhenium is one of the rarest elements in the Earth's crust. It has one of the highest melting and boiling points of any element. It resembles manganese and technetium chemically and is mainly obtained as a by-product of the extraction and refinement of molybdenum and copper ores.